95 GBaud transponders, equipped with probabilistic shaping and advanced FEC, improve backbone networks by reducing power and increasing spectral efficiency. We review network expectations and observations for this class of transponder.

A record capacity of 24 Tbps on a 6,644 km trans-Atlantic deployment using 16QAM is enabled by synthesized subcarriers, FEC gain sharing, multi-carrier wavelocking, and large-area, high dispersion fiber. Computer assisted optimization and automated protection facilitate full-fill deployments becoming prevalent as submarine cables enter the SDM era.

Real-time, error-free 16QAM transmission at a record spectral efficiency of 6.21 b/s/Hz enables transatlantic (6,644 km) fiber capacity of 26.2 Tbps, using precision, multi-carrier common wavelocking; digitally synthesized subcarriers; near-Nyquist pulse shaping; and large-area, positive dispersion fiber.

We demonstrate multi-channel InP-based coherent transmitter and receiver photonic integrated circuits hybrid integrated with SiGe driving and amplifying electronics both capable of operating at 880 Gb/s and the transmitter alone up to 1 Th/s per wave. These hybrid assemblies demonstrate optical transmissions across a commercial line system at distances from 200 to 1400 km, with symbol rates between 66-100 GBd, utilizing 16-, 32-, and 64-QAM modulation formats. Additionally, we demonstrate a back-to-back transmission from the TxPIC assembly to a reference receiver at 100 GBd x 32QAM, a 1 This per wavelength capability.

We propose to demonstrate automated service management and automated optical power controls over Infinera and Lumentum Open Optical Line Systems using an Infinera Layer-0 SDN controller.

Key advances which enabled the InP photonic integrated circuit (PIC) and the subsequent progression of InP PICs to fully integrated multichannel DWDM system-on-chip (SOC) PICs are described. Furthermore, the current state-of-the-art commercial multichannel SOC PICs are reviewed as well as key trends and technologies for the future of InP-based PICs in optical communications.

We show real-time measurement of error-free superchannel transmission over more than 10,500 km of large-area fiber at a spectral efficiency of 4.66 b/s/Hz, utilizing subcarrier based signal processing optimized at 5.4 GBd.

We demonstrate a fully integrated multi-channel InP-based coherent transmitter photonic integrated circuits (PICs) with extended C-band tunability, operating at 33 and 44 Gbaud per channel under 16-QAM dual-polarization modulation. PICs are demonstrated integrating up to 14-channels enabling multi-Tb/s total PIC capacities.

We introduce a scalable PIC and module platform with full C-band tunability per-channel operating at 33 and 44 Gbaud per channel under 16-QAM dual-polarization mode and demonstrate transmitter and receiver integration up to 14-channels enabling multi-Tb/s total PIC capacities.

We present a review of next generation optical transmission systems making use of flexible capacity superchannels based upon photonic integrated circuits, Flexgrid WSS based ROADMs, and next generation multiplexing architectures.

The goal of long haul DWDM transmission is to deliver error-free digital information at extremely high data rates and over very long distances, ideally without the need for regeneration of the signal. Forward error correction (FEC) is a method of encoding a signal with additional overhead information so that optical receivers can detect and correct errors that occur in the transmission path. The latest enhancement for FEC is the use of a soft decision algorithm that significantly improves the optical reach. This study evaluates the impact of soft decision forward error correction (SD-FEC) technology upon network design and economics in a long haul optical transport network. The network study shows that the SD-FEC technology not only reduces the total cost of ownership, but also simplifies the network design. Real-world network models are utilized to quantify and compare results.

This paper proposes CDC ROADM architecture compatible with emerging DWDM super-channel technology. A real world network model is used to quantify that this architecture requires fewer network components leading to less capital and operational costs.

A coherent MODEM is implemented with FEC payload and checksum distributed between two PM-QPSK optical channels spaced at 200 GHz. Real-time experiments verify PDL and PMD penalties are 40-50% higher without FEC gain sharing.

Combined effects of distributed polarization mode dispersion (PMD), polarization dependent loss (PDL), and amplified-spontaneous-emission noise are considered in analyzing the bit error rate penalty of coherent transmission systems utilizing multiple-input-multiple-output equalization and least-mean-squared adaptation. A semianalytical model is used to evaluate system penalty at 10(-5) probability of occurrence. It is found that a large amount of PMD in the fiber can significantly reduce the PDL penalty. Similarly, intentionally introducing PMD in the transmitter can also reduce the PDL penalty.

Benefits of intra-superchannel spectral-equalization are demonstrated in a production 8Tbps system. ~1.2dB OSNR improvement and ~4.5dB reduction in power-spread is measured relative to inter-superchannel equalization. Tradeoff between OSNR and nonlinearity dictates the net reach improvement.

Super-channels promise high-bandwidth transmission while decoupling channel capacity from baud rate. Photonic Integrated Circuits (PICs) are optimal for delivering super-channels at over 100 Gb/s, with flexibility in modulation format, baud rate, dispersion tolerance, and reach.

Recent emergence of coherent optical modem has solved a number of difficult problems in optical transmission, resulting in 10× increase in capacity. The latest research of super-channels further increases spectral efficiency and network flexibility.

We present a 500 Gb/s, PM-QPSK Photonic Integrated Circuit (PIC) based MODEM, software configurable into 250 Gb/s TCM mode, as a flexible optical network building block, operating over a 6000 km link with flex ROADMs.

In this paper we review the design and performance of multi wavelength, 112Gbit/s per wavelength, polarization multiplexed QPSK coherent photonic integrated transmitters and receivers for implementing terabit/s superchannels.